More than three integrals occur when additional symmetry or degeneracy restricts motion beyond a generic three-frequency invariant torus. In a time-independent central gravitational potential, energy and the three components of specific angular momentum are four generically independent isolating integrals. They fix the orbital plane as well as the radial-motion parameters. A nonclosed planar rosette typically has two-dimensional orbit closure, rather than a three-dimensional invariant torus.
The Kepler orbit is a stronger example. In addition to and , the conserved Laplace-Runge-Lenz vector
fixes the apsidal direction. Its constraints and leave five independent integrals among . It is a maximally superintegrable Hamiltonian system, with closed nondegenerate bound orbits.
More than three integrals need not form a set of Poisson-commuting functions; the three-integral limit applies to an independent commuting set, rather than to every conserved orbit constraint. At a nonstationary point in six-dimensional phase space, integral gradients annihilate the nonzero flow vector, so at most five are independent. This explains the isolating integrals and orbital closure dimension count. A resonance on one isolated orbit does not by itself prove an additional smooth global integral on a neighborhood.
An isolating integral restricts the accessible phase space to a lower-dimensional regular level set. For functionally independent integrals of motion , the differentials must be independent, and impose independent restrictions. In six-dimensional phase space the common regular level set has dimension . Nonisolating orbit labels or multivalued constants do not further reduce the closure explored by the motion. This is the isolating integrals and orbital closure dimension distinction.